The invention relates generally to troffer light fixtures, more particularly to troffer light fixtures having a removable hinged door or a removable hinged louver, and even more particularly to replacement doors or louvers for retrofitting troffer light fixtures, doors and louvers that are already installed.
A troffer light fixture is a generally rectangular or square tray-like housing comprising a top body wall and four shorter side walls that is installed in or on a ceiling in an inverted manner such that it is open toward the floor. Electrical components, ballast, hardware and the like are affixed to the top body wall and/or the side walls. These components operate the light producing elements, typically one or more elongated or U-shaped tubular fluorescent lamps. A removable panel member typically comprises either a diffusion lens or a louver and is retained by the troffer housing by hinge and latch members, the panel being removable to allow replacement of the fluorescent lamps and other electrical components when needed. The panel member may have many configurations, such as flat, curved, angled, segmented, etc. In some troffers, the removable panel member further comprises a relatively rigid peripheral frame assembly with hinge members and latch members that are received by short slots or openings in the troffer housing assembly. With this structure, the troffer door assembly or louver can be unlatched and pivoted open on the hinge members, and the hinge members are often separable from the troffer housing assembly such that the entire door panel or louver may be removed.
Light emitting diodes (LEDs) have been developed that are less expensive to operate and have a much greater working life than incandescent bulbs and fluorescent lamps, and when assembled into arrays of multiple LEDs have been found to be excellent replacements for the tubular fluorescent lamps in troffer assemblies. An array of LEDs mounted to a relatively rigid support structure is often referred to as an LED light bar. The LEDs are powered by a power supply commonly known as a driver. The driver and LED light bar are collectively an LED system and replace the electrical components, ballast, hardware and the like used in fluorescent fixtures. Because LED systems produce significant heat during operation, the support structure for the LED system is usually constructed to function as a heat sink and/or heat radiating member such that heat is conducted away from the LED system.
The current method of retrofitting most installed troffer light fixtures to replace the fluorescent lamps and associated electrical components with one or more LED light bars involves removing the non-essential electrical components, ballast and hardware mounted within the troffer housing so that there is enough room, clearance and exposed surfaces for installation of the LED light bars, then mounting the LED light bars or panels to the interior body wall or the top/side walls of the troffer housing using mechanical fasteners. This is a time consuming and expensive process.
It is an object of this invention to improve on the methodology of retrofitting troffer light fixtures by providing a novel troffer door assembly wherein one or more LED light bars are directly affixed to the peripheral frame in a manner allowing for conduction of heat from the LED light bars to the frame. The peripheral frame thereby functions as a heat sink in addition to the light bar support structure. Furthermore, the LED light bars are rigidly connected to the peripheral frame in a manner that provides increased structural integrity to the troffer door assembly. It is a further object to provide a troffer door assembly wherein the peripheral frame is formed with elongated exterior slots to receive the latch members and the hinge members in a manner that allows their positions along the frame to be adjusted as required to correspond to the variety and location of latch and hinge openings that may be encountered in the field during the retrofit process. It is a further object to provide a troffer door assembly having elongated interior slots adapted to receive therein all or some of the peripheral edges of the panel member. These objects, along with other objects not expressly set forth here, will be apparent from the detailed disclosure to follow.